Not Applicable
Not Applicable
This invention relates to the field of intravascular medical devices, and more particularly to the field of catheters such as angioplasty, neurological and guide catheters, among others. Catheters may be used in various medical procedures such as percutaneous transluminal angioplasty (PTA), percutaneous transluminal coronary angioplasty (PTCA) as well as in procedures involving the placement of medicines and medical devices within the body. The present invention is directed to all forms of catheters which may be advanced through a body lumen or vessel. Some examples of catheters are over-the-wire (OTW) catheters, such as are described in U.S. Pat. No. 5,047,045; single-operator-exchange (SOE) balloon catheters, such as are described in U.S. Pat. No. 5,156,594 and U.S. Pat. No. 5,549,552. Other examples of catheters which may incorporate the unique features of the present invention are also described in U.S. Pat. Nos. 5,938,653, 5,897,537, among others.
Many procedures make use of a guide catheter positioned within the vascular system of a patient. The guiding catheter assists in transporting a balloon dilation catheter, or other form of treatment catheter, to the portion of the vessel requiring treatment or inspection. The guide catheter is urged through the vasculature of the patient until its distal end is proximate the restriction. The balloon catheter may then be fed through a lumen in the guide catheter.
Balloon catheters may be used to widen a vessel into which the catheter is inserted by dilating the blocked vessel, such as in an angioplasty procedure. Balloon catheters may also be used to expand and/or seat a medical device such as a stent, graft, stent-graft, vena cava filter or other implantable medical device at a desired position within a body lumen. In such applications, fluid under pressure is supplied to the balloon through an inflation lumen in the catheter, thereby expanding the balloon.
Intravascular diseases are commonly treated by relatively non-invasive techniques such as PTA and PTCA. These angioplasty techniques typically involve the use of a balloon catheter. In typical PTCA procedures, a guiding catheter is percutaneously introduced into the cardiovascular system of a patient through a vessel and advanced through therein until the distal end thereof is at a desired location in the vasculature. A guide wire and a dilatation catheter having a balloon on the distal end thereof are introduced through the guiding catheter with the guide wire sliding through the dilatation catheter. The guide wire is first advanced out of the guiding catheter into the patient""s coronary vasculature and the dilatation catheter is advanced over the previously advanced guide wire until the dilatation balloon is properly positioned across the lesion. Once in position across the lesion, the flexible, expandable, preformed balloon is inflated to a predetermined size with a liquid or gas at relatively high pressures, to radially compress the arthrosclerotic plaque of the lesion against the inside of the artery wall and thereby dilate the lumen of the artery. The balloon is then deflated to a small profile so that the dilatation catheter may be withdrawn from the patients vasculature and blood flow resumed through the dilated artery.
In angioplasty procedures of the kind described above, there may be injury to or restenosis of the artery, which either necessitates another angioplasty procedure, a surgical by-pass operation, or some method of repairing or strengthening the area. To strengthen the area and help prevent restenosis, a physician can implant an intravascular prosthesis for maintaining vascular patency, commonly called a stent, inside the artery at the lesion.
A stent is a generally cylindrical prosthesis introduced via a catheter into a lumen of a body vessel in a configuration having a generally reduced diameter and then expanded to the diameter of the vessel. In its expanded configuration, the stent supports and reinforces the vessel walls while maintaining the vessel in an open, unobstructed condition.
Stents are generally tubular in configuration, open ended and are expandable between a generally unexpanded insertion diameter and an expanded implantation diameter. Stents are commonly placed or implanted by a mechanical transluminal procedure.
Self-expanding, inflation expandable and hybrid stents are well known and widely available in a variety of designs and configurations. Self-expanding stents may be retained on a catheter shaft prior to delivery through the use of a sheath, sleeve(s), sock or other retaining member which function to maintain the stent is a reduced diameter configuration during advancement of the catheter to the stent deployment site. Inflation expandable and hybrid stents may be crimped to their reduced diameter about the delivery catheter, then maneuvered to the deployment site and expanded to the vessel diameter by fluid inflation of a balloon positioned between the stent and the delivery catheter. All types of stents however may be retained in a reduced profile configuration by the one or more sheathes, sleeves, sock or other retaining members.
Some examples of stents are described in the following U.S. patent references: U.S. Pat. Nos. 4,733,665; 5,019,090; 4,503,569; 4,512,338; 4,732,152; 4,848,343; 5,234,456; 5,443,458; and 5,258,020.
Stent delivery and deployment assemblies are known which utilize restraining means that overlie the stent during delivery. U.S. Pat. No. 4,950,227 to Savin et al., relates to an inflation expandable stent delivery system in which a sleeve overlaps the distal or proximal margin (or both) of the stent during delivery. During inflation of the stent at the deployment site, the stent margins are freed of the protective sleeve(s). U.S. Pat. No. 5,403,341 to Solar, relates to a stent delivery and deployment assembly which uses retaining sheaths positioned about opposite ends of the compressed stent. The retaining sheaths of Solar are adapted to tear under pressure as the stent is radially expanded, thus releasing the stent from engagement with the sheaths. U.S. Pat. No. 5,108,416 to Ryan et al., describes a stent introducer system which uses one or two flexible end caps and an annular socket surrounding the balloon to position the stent during introduction to the deployment site.
Some other examples of stent delivery assemblies are described in the following U.S. patent references: U.S. Pat. Nos. 5,571,135; 5,445,646; 5,571,168; 5,702,418; 5,733,267; 5,817,101; 5,893,868; 5,944,726; 5,989,280; 5,980,530; 5,980,533; 5,968,052; 5,968,069; 6,007,543; 6,042,588; 6,056,759; 6,059,813; 6,066,155; 6,068,634; 6,113,608; 6,120,522; 6,117,140; 6,139,524; 6,168,617; 6,206,888; 6,254,609; 6,221,097; 6,238,402; and 6,270,504.
In many catheters, particularly in many of those used in medical device delivery procedures, a catheter may be equipped with one or more members including but not limited to: sheaths, sleeves, socks, collars, bands an/or any other member, collectively and hereinafter referred to generically as xe2x80x9csleevesxe2x80x9d. In some cases, the sleeve(s), or a portion thereof, may be engaged or otherwise secured to a portion of the catheter shaft and/or portion of a balloon, in a variety of manners including, frictional engagement, adhesive engagement, chemical and/or thermal bonding or welding, etc.
However, many securement methods and configurations have difficulty properly securing a member to a catheter or balloon where the respective materials are incompatible. In addition, some sleeves, when secured to a catheter using prior a securement methods have a tensile strength which is less than desired. As a result, it would be desirable to provide a catheter assembly with a member engagement method and/or configuration particularly suited for bonding components such as sleeves and/or other types of members to the catheter shaft or balloon waist regardless of the material composition of the catheter, balloon and/or components. In addition it would be desirable to provide a securement method which results in a sleeve having a greater tensile strength than that which is provided by some prior methods.
All U.S. patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
The invention in various of its embodiment is summarized below. Additional details of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
The abstract provided herewith is intended to comply with 37 CFR 1.72 and is not intended be used in determining the scope of the claimed invention.
The present invention may be embodied in a variety of different forms. At least one embodiment of the invention is directed to a collar for use with a catheter. Preferably the collar is used with a balloon catheter having one or more components such as sleeves mounted thereon herein after collectively referred to as sleeves. The inventive collar is preferably constructed from the same material as the balloon. The collar is disposed about the sleeve where the sleeve overlaps the balloon waist. A heat source such as an annular laser, heats the collar and the underlying materials to a point where the collar material is fused or welded to the balloon waist. As a result, the portion of the sleeve overlapped by the collar and balloon waist may be encased within the now fused collar and balloon waist materials. In a preferred embodiment, the portion of the sleeve overlapped by both the collar and balloon waist is fused or welded to one or both of the collar and balloon material.
Details of these and other embodiments of the invention are discussed below.